Non-professional home sports, as well as some other professional sport branches are characterized by the fact that the individual usually trains alone, some times with no real opponent, which could stimulate and improve his performance, like time of exercise or effort. For example, in basic training exercises such as sit-ups, push-ups, or training with bar bells, the individual exercises for a certain period of time or till he gets tired. The result of the exercise in most cases is the number of repeated sit-ups or push-ups. The scores usually are not recorded anywhere and there is no proper follow up. Furthermore, there is no sufficient motivation in training alone. Some times, the counting is not accurate, because the exerciser concentrates on making the effort, rather than on the counting and the quality of the exercise.
The similar situation applies to physical activities associated with long distance moves, e.g. walking running, jogging, skiing etc.
In such cases, it would be desirable that the exercising individual is provided with a device that monitors his training and advises him about the performance for example by producing an audio/visual signal. This device could also keep a record of the current and previous performances and thus motivate and encourage the exerciser.
The above concept is not new and there is known in the art various fitness-monitoring devices, in which the above concept is implemented.
For example in U.S. Pat. No. 5,655,997 and 5,785,632 is disclosed an apparatus and system for providing feedback to a user of a weight stack machine. In this apparatus a means for sensing weight for determining the number of weights lifted is provided as well as encoder means for detection the motion of the weight during a lift. An electronic detector is operatively coupled to the weight sensor and the encoder for computing data describing the number of weight lifts.
In WO 96 96/29121 is disclosed a weight training apparatus for measuring a displacement in an exercise apparatus used for training or for rehabilitation. The apparatus comprises a peg for selecting part of a stack weights and this peg acts as a transmitter enabling a sensor system to sense the selected number of weights as well as the distance traveled by the weights, the time taken and their speed.
The apparatus comprises also a mechanism with scales attached to the machine along the travel route of the weights.
The disadvantage of both above-mentioned devices lies in the fact that they require sensing means, which should be directly attached to the weights for sensing the weights travel. This condition renders the above devices inconvenient in installation, limits their portability and excludes possibility for plug & play mode of operation.
In U.S. Pat. No. 4,387,437 is disclosed a runners watch, which is to be worn on the wrist of the wearer. The watch is provided with a sensor detecting the stride of the wearer when the wearer is running or jogging and with a circuitry, which calculates the distance traveled and the computed rate of travel. The disadvantage of this device is its limited applicability and insufficient accuracy, since a sensor employed in it is a mechanical pendulum, which can not sense travel not associated with strides, e.g. boating, skiing etc.
In U.S. Pat. No. 5,689,099 is disclosed speed/distance measuring assembly for runner, which measures angular displacement of the foot and the distance of the torso from a reference point. This approach is also not suitable for such displacements, like boating, horse riding or any other displacements, which are not associated with angular foot displacement.
In U.S. Pat. No. 4,962,469 is disclosed exercise measurement instrument, employing an acceleration sensor, connected to an amplifier. An output waveform signal of the acceleration sensor is supplied to the amplifier. The instrument is provided also with manually operable switching means for selecting one exercise mode out of plurality of modes available, amplifier gain-control means coupled to the switching means for varying the gain in accordance with the selected mode and exercise-measuring means for measuring exercise data on the basis of the waveform signal and announcing means for displaying the data measured. The disadvantage of this instrument is associated with the fact that the acceleration sensor resides not separately from the rest of the components, e.g. display means, data-entry means etc. but in the same enclosure. In such a configuration the accelerometer can not be always positioned accurately in the movement direction since each rotation or linear displacement of the instrument causes an error in the acceleration sensor reading, and consequently the velocity and position are calculated erroneously as well.
In U.S. Pat. No. 5,724,265 is described a system and method for measuring movement of objects, e.g. the distance traveled, speed and height jumped while running or walking. This system employs accelerometers and rotational sensors placed in the sole of one shoe along with an electronic circuit, which calculates the distance and height of each step. A radio frequency transmitter sends this data to a central receiving unit, which is formed as a wristwatch. The receiving unit calculates an output speed based upon step-distance and elapsed time and the total distance traveled. Unfortunately the approach implemented in the above patent is not suitable for monitoring of skiing, horse riding and boating.
Besides, location of the sensor unit in the shoe might be associated with limited reliability of operation and insufficient accuracy of measurement.
Thus despite there are known in the art plenty of methods and devices enabling an individual to monitor and measure his performances during physical activity, nevertheless there is still felt a strong need in a new and improved system and method, which is free of the above-mentioned disadvantages of the known in the art solutions.